1. Field of the Invention
The present invention relates to the field of data storage in a computer system and, more particularly, to prevention of unauthorized changes to data stored in a computer system.
2. Description of the Related Art
Computer technology is continuously advancing, resulting in modern computer systems that provide ever-increasing performance. One result of this improved performance is an increased use of computer systems by individuals in a wide variety of business, academic and personal applications. With the increased use of and demand for computer systems, a large number of manufacturers, developers, and suppliers of computer systems, components, and software have come into existence to service the demand.
The large number of manufacturers, developers, and suppliers, combined with the flexibility afforded them due to the advances in technology, has resulted in a wide range of methods by which computer systems operate. Typically, in order for different components within a computer system to work together effectively, each must agree on certain specific operating parameters. Often, standards or specifications are adopted or agreed upon by various industries or groups of companies which define certain operating parameters. Thus, if two components comply with the same standard(s) or specification(s), then the two components should be able to work together effectively in the same system.
For example, one such standard is the Plug and Play BIOS basic input/output system! Specification (version 1.0A, May 5, 1994). A component which conforms to the Plug and Play BIOS Specification should work properly in a system which also complies with the Plug and Play BIOS Specification by simply interconnecting the components to the system. Components that do not comply with the Plug and Play BIOS Specification may require additional configuration steps to be taken by the user before they function properly with one another.
Another current standard is the Desktop Management BIOS Specification (version 2.0, published Mar. 6, 1996) (hereinafter referred to as the DMI BIOS Specification), the entirety of which is incorporated herein by reference. This specification includes a Desktop Management Interface (DMI). The DMI BIOS Specification provides, among other advantages, general purpose nonvolatile (GPNV) data areas which can be accessed to store various data by various applications running on the system.
The DMI BIOS Specification, however, lacks suitably flexible mechanisms to prevent an application from performing an unauthorized modification of data stored in one of these GPNV data areas. For example, a GPNV data area may store vital manufacturing data the modification of which may be done for fraudulent purposes. Thus, it would be beneficial to provide mechanisms for restricting write access to selected GPNV data areas to prevent unauthorized changes to the data stored therein.
Additionally, in order to maintain compliance with the DMI BIOS Specification, any protection against unauthorized updates to GPNV data areas must not violate the DMI BIOS Specification.